Devices that rely on an exothermic reaction as a self-contained heat source are familiar to consumers in the form of, for example, disposable hand and foot warmers. These devices include a reaction mixture that generates heat when water or oxygen is introduced into the reaction mixture. Devices that produce heat are also used in medical situations, such as in the ablation of tissues or cells, to cauterize wounds, and to render various surfaces substantially aseptic. Cauterization is a medical technique used to stop blood flow and help seal the surface of a wound. Various conventional devices for carrying out cauterization include electrocauterizers and laser cauterizers that act to destroy tissue while rapidly aiding the coagulation of blood vessels which have been cut in the wound. These devices do not typically rely on an exothermic chemical reaction as the source of heat.
Heat can also be used to render surfaces aseptic. For example, a variety of devices and methods have been used to sterilize surgical instruments (such as autoclaves) and other surfaces, such as a patient's skin or a surgeon's hands, and examples of such devices that are non-heat based include antiseptic wipes, antibacterial solutions, etc. Sterilization techniques for instruments generally use heat for extended periods of time as an aid in destroying bacterial and other pathogens on the instruments. Sterilization techniques for use with human skin or other surfaces typically rely on a chemical interaction between the material being applied and the pathogens themselves to destroy the pathogens.
Medical systems such as bandages are conventionally used to slow bleeding by providing pressure to a wound and by assisting with the blood's natural coagulation process that involves platelets in the blood and fibrin. Bandages are also used to help prevent additional bacterial and other harmful materials from entering an open wound. Bandages used to cover wounds generally include a portion either directly coupled to the bandage or coupled to the wound through the bandage that is sterile, such as a gauze pad or other sterile structure.